I would advise you to visit the a pulmonologist or a MD general medicine so that she can be examined and further examination can be done such as X-Ray, CBC, AEC etc to find the underlying cause and have it treated accordingly. If she develops another episode as such visit the nearest casualty so that she can be checked with stethescope and based on the findings given a nebulisation.
Next Steps
Follow the steps as advised
Health Tips
If condition persists or worsens visit the ER at the earliest